2,4-Dihydroxy-4&#39;-(substituted amino)-diphenylamines

ABSTRACT

New compounds suitable for dyeing keratin fibres, especially human hair, are described. The compounds have the formula: ##STR1## or an acid addition salt thereof, in which formula either R 1  and R 2  form, together with the nitrogen atom to which they are bonded, a morpholino or piperidino ring and R represents a hydrogen atom, or R 1  represents a hydrogen atom, R 2  represents a furfuryl or methoxyethyl radical and R represents a hydrogen atom or a methyl radical.

DESCRIPTION

The present invention relates to certain 2,4-dihydroxydiphenylamines.These diphenylamines can be used as dyestuff precursors in the oxidativedyeing of keratin fibres and especially of human hair.

The compounds according to the present invention are the2,4-dihydroxydiphenylamines of the formula: ##STR2## and also their acidsalts, in which formula either the substituents R₁ and R₂ form, togetherwith the nitrogen atom to which they are bonded, a morpholino orpiperidino ring and R represents a hydrogen atom, or R₁ represents ahydrogen atom, R₂ is a furfuryl or methoxyethyl radical and R representsa hydrogen atom or a methyl radical.

The present invention also provides a composition suitable for dyeingkeratin fibres, and especially human hair, which comprises, in solution,at least one 2,4-dihydroxydiphenylamine of the formula (I).

The dyeing compositions according to the invention can also contain atleast one other diphenylamine and, in particular, at least one diphenylof the formula: ##STR3## or an acid salt thereof, in which formula: R₁and R₄, which are identical or different, each represent a hydrogen orhalogen atom or a lower (i.e. of 1 to 6 carbon atoms) alkyl, loweralkoxy, acylamino or ureido group, R₂ and R₃, which are identical ordifferent, each represent a hydrogen or halogen atom or a lower alkyl,lower alkoxy, amino, N-alkylamino, N-hydroxyalkylamino, acrylamino,N-carbamylalkylamino or ureido group, R₅ represents a hydrogen orhalogen atom or a lower alkyl or lower alkoxy group, R₆, R₇ and R₈,which are identical or different, each represent a hydrogen or halogenatom or a lower alkyl or lower alkoxy group, Y represents a hydroxyl oramino group and Z represents a hydroxyl group or a group of the formula##STR4## in which R₉ and R₁₀, which are identical or different, eachrepresent a hydrogen atom or a lower alkyl group which is unsubstitutedor substituted by carbamyl, amino, di(lower alkyl) amino, acylamino,lower alkylsulphonamido, arylsulphonamido, sulpho, piperidino ormorpholino or hydroxyalkyl group of 2 to 6 carbon atoms.

The dyeing compositions according to the invention can also contain atleast one direct dyestuff and preferably a nitrobenzene dyestuff, suchas 3-nitro-4-aminophenol, 3-nitro-4-N-(β-hydroxyethyl)-aminophenol,3-nitro-6-N-(β-hydroxyethyl)-aminophenol and3-nitro-4-N'-methylamino-N,N-(β-hydroxethyl)-aniline.

The dyeing compositions according to the invention can also contain atleast one dyestuff of the hydroxynaphthoquinone type, such as2-hydroxy-1,4-naphthoquionone or 5hydroxy-1,4-naphthoquione.

The compositions according to the invention can be used as conventionaldye compositions for keratin fibres and especially human hair. Thecompositons according to the invention can, however, also be used aswavesetting lotions for human hair.

When the compositions according to the invention are used asconventional oxidative dye compositions the said compositions cancontain, in addition to the compound (or compounds) of the formula (I)at least one of the following:

(1) para-phenylenediamines and, in particular, paraphenylenediamines ofthe formula: ##STR5## or the corresponding acid salts, in which formulaR₁, R₂ and R₃ are identical or different and represent a hydrogen atom,an alkyl radical having from 1 to 4 carbon atoms or an alkoxy radicalhaving from 1 or 2 carbon atoms, and R₄ and R₅ are identical ordifferent and represent a hydrogen atom, and alkyl or hydroxyalkylradical, an alkoxyalkyl radical in which the alkoxy group contains from1 or 2 carbon atoms, or a carbamylalkyl, mesylaminoalkyl,acetylaminoalkyl, ureidoalkyl or carbethoxyaminoalkyl radical, the alkylgroups in R₄ and R₅ having from 1 to 4 carbon atoms, with the provisothat R₁ and R₃ represent hydrogen if R₄ and R₅ do not both represent ahydrogen atom;

(2) para-aminophenols and, in particular, those which correspond to theformula: ##STR6## or the corresponding acid salts, in which formula R₆represents a hydrogen atom, an alkyl radical containing from 1 to 4carbon atoms, or a halogen atom such as chlorine or bromine;

(3) couplers and, in particular, meta-phenylenediamines such as thosedescribed in U.S. Pat. No. 4,125,367, the disclosure of which is herebyincorporated by reference, resorcinol, meta-aminophenol,2-methyl-5-aminophenol, 2-methyl-5-N-(β-hydroxyethyl)-aminophenol,6hydroxybenzomorphonline, 2,6-dimethyl-5-acetylaminophenol,2-methyl-5-carbethoxyaminophenol, 2-methoxy-5-carbethoxyaminophenol and2-methyl-5-ureidophenol;

(4) ortho-phenylenediamines and ortho-aminophenols optionally containingnuclear substituents and/or substituents on the amine groups, it beingpossible for these products, by means of complex oxidation mechanisms,to lead to new coloured compounds, either by cyclisation with themselvesor by reaction with para-phenylenediamines;

(5) oxidative dyestuff precursors having benzene structures, whichcontain at least three groups which are OH, OCH₃ or substituted orunsubstituted amino groups, such as2,6-diamino-4-N,N-diethylamino-phenol (for example in the form of thetrihydrochloride), 2,5-diamino-4-methylphenol and trihydroxybenzene; and

(6) customary adjuvants such as penetrating agents, foaming agents,thickeners, antioxidants, alkalising agents, perfumes, sequesteringagents and film-forming products.

The pH of the dyeing compositions according to the invention should be abasic pH, for example from 8 to 11.5. Amongst the alkalising agentswhich can be used to provide this, there may be mentioned ammonia,alkylamines, such as ethylamine or triethylamine, alkanolamines, such asmono-, di- or triethanolamine, alkylalkanolamines, such asmethyldiethanolamine, sodium hydroxide or potassium hydroxide and sodiumcarbonate, potassium carbonate or ammonium carbonate.

Anionic, cationic, non-ionic or amphoteric water-soluble surface-activeagents can also be included in the compositions according to theinvention. Amongst the surface-active agents which can be used inparticular, there may be mentioned alkylbenzenesulphonates,alkylnaphthalenesulphonates, sulphates, ether-sulphates and sulphonatesof fatty alcohols, quaternary ammonium salts, such astrimethylcetylammonium bromide and cetylpyridinium bromide,diethanolamides of fatty acids, polyoxyethyleneated acids and alcholsand polyoxyethyleneated alkylphenols. The surface-active products arepreferably present in the compositions according to the invention in anamount from 0.5 to 30% by weight and advantageously from 4 to 25% byweight.

Organic solvents can also be added to the compositions according to theinvention in order to solubilise compounds which are not otherwisesufficiently soluble in water. Amongst the solvents which canadvantageously be used, there may be mentioned, by way of example,ethanol, isopropanol, gylcerol, glycols, such as butylglycol, ethylenegylcol and propylene glycol, and diethylene glycol monoethyl ether andmonomethyl ether. The solvents are advantageously present in thecompositions in an amount from 1 to 40% by weight and preferably from 5to 30% by weight.

Suitable thickeners which can be included in compositions according tothe invention include sodium alginate, gum arabic, cellulosederivatives, such as methylcellulose, hydroxyethylcellulose,hydroxypropylmethylcellulose and the sodium salt ofcarboxymethylcellulose, and acrylic acid polymers as well as inorganicthickeners such as bentonite. The thickeners are preferably present inan amount from 0.5 to 5% by weight, and advantageously from 0.5 to 3% byweight, relative to the total composition.

The antioxidants which can be included in the compositions according tothe invention may be, for example, sodium sulphite, thioglycolic acid,sodium bisulphite, ascorbic acid and hydroquinone. These antioxidantscan be present in the compositions in an amount of, say, 0.05 to 1.5% byweight, relative to the total weight of the composition.

In general, the compounds of the formula (I) are present in the dyeingcompositions according to the invention in an amount from 0.001% to 5%by weight, relative to the total weight of the composition.

The dyeing compositions according to the invention can be in the formof, for example, a liquid, a cream, a gel or an aerosol or in any otherform which is suitable for dyeing keratin fibres.

The dyeing compositions in which the diphenylamines of the formula (I)are present can be applied as conventional oxidative dyes with orwithout the addition of an oxidising agent, for example hydrogenperoxide, prior to application. As with similar compositions, thecompositions according to the invention are suitably kept in contactwith the hair for 5 to 30 minutes, after which the treated hair isrinsed and shampooed.

When the compositions according to the invention are used as wavesettinglotions, they are generally applied to hair which has been washedbeforehand and the hair is then set in waves and dried with hot air.Wavesetting lotions are usually aqueous-alcoholic solutions containingat least one cosmetic resin and the lotions of this invention aregenerally in this form. Suitable cosmetic resins includepolyvinylpyrrolidone resins, crotonic acid/vinyl acetate copolymers,vinylpyrrolidone/vinyl acetate copolymers and maleic anhydride/butylvinyl ether copolymers which have been semi-esterified with an alcoholsuch as methanol, ethanol or butanol. The cosmetic resin is usuallyemployed in an amount from 1 to 3% by weight.

The alcohols which can be used for producing the wavesetting lotionsaccording to this invention are, in particular, low molecular weightalcohols and preferably ethanol or isopropanol; these alcohols aregenerally used in an amount from 20 to 70% by weight.

The diphenylamines of the formula (I) can be prepared by an anaerobicreaction, with 1,2,4-trihydroxybenzene or trihydroxytoluene, of apara-phenylenediamine in which one of the amine groups is primary and inwhich the other amine group is secondary or tertiary. The desireddiphenylamines can be isolated from the reaction medium for use in thedyeing compositions according to the invention, but it is also possibleto use the reaction medium directly, after sufficient reaction time haselapsed, without isolation of the diphenylamines of formula (I). Thisreaction medium can then be used in conventional oxidative dyeing, withor without the prior addition of hydrogen peroxide.

The following Examples further illustrate the present invention.

EXAMPLE 1 Preparation of2,4-dihydroxy-4'-N-(β-methoxyethylamino)-diphenylamine dihydrochloride##STR7##

The following solution is prepared:

    ______________________________________                                        Trihydroxybenzene (1,2,4)                                                                             18.9    g                                             4-N-(β-Methoxyethylamino)-aniline                                        dihydrochloride         35.85   g                                             Sodium sulphite         7.5     g                                             Sodium carbonate        33      g                                             Water   q.s.p.          750     g                                             ______________________________________                                    

This solution is kept under nitrogen for one month at 40° C. The oilyproduct which has deposited at the bottom of the reaction medium isseparated off by decantation, it is washed with a dilute aqueoussolution of sodium sulphite, and hydrochloric acid (d=1.18) is thenadded thereto. The expected product precipitates in the form of thecrystalline dihydrochloride. After recrystallisation with the aid of 5 Nhydrochloric acid solution, the product is filtered off and dried invacuo. It melts at 180° C. with decomposition.

Elementary analysis of the product obtained gives the following results:

    ______________________________________                                                  CALCULATED                                                          ANALYSIS  FOR C.sub.15 H.sub.20 N.sub.2 O.sub.3 Cl                                                       FOUND                                              ______________________________________                                        C%        51.87            51.65                                              H%        5.80             5.97                                               N%        8.07             8.20                                               Cl%       20.42            19.93-20.07                                        ______________________________________                                    

EXAMPLE 2 Preparation of2,4-dihydroxy-5-methyl-4'-N-(B-methoxyethylamino)-diphenylaminedihydrochloride ##STR8##

The following solution is prepared:

    ______________________________________                                        Trihydroxytoluene (1,2,4)   7      g                                          4-N-(β-Methoxyethylamino)-aniline dihydrochloride.                                                   11.95  g                                          Sodium sulphite             2.5    g                                          Sodium carbonate            11     g                                          Water   q.s.p.              250    g                                          ______________________________________                                    

This solution is kept in the absence of air for one month at 40° C. Theoily product which has deposited at the bottom of the reaction medium isseparated off by decantation, it is washed with a dilute solution ofsodium sulphite, and hydrochloric acid (d=1.18) is then added thereto.The expected dihydrochloride precipitates in crystalline form. It isfiltered off and then recrystallised from 60 ml of 4 N hydrochloricacid. After drying in vacuo, the product melts at about 194° C. withdecomposition.

Elementary analysis of the product obtained gives the following results:

    ______________________________________                                                  CALCULATED                                                          ANALYSIS  FOR C.sub.16 H.sub.12 N.sub.2 O.sub.3 Cl.sub.2                                                 FOUND                                              ______________________________________                                        C%        53.19            53.17                                              H%        6.14             6.28                                               N%        7.75             7.60                                               Cl%       19.62            19.83                                              ______________________________________                                    

EXAMPLE 3 Preparation of2,4-dihydroxy-4'-tetrahydrofurfurylaminodiphenylamine dihydrochloride##STR9##

The following solution is prepared:

    ______________________________________                                        Trihydroxybenzene         7.5     g                                           4'-N-Furfurylaminoaniline dihydrochloride                                                               5.3     g                                           Sodium sulphite           1.5     g                                           Sodium carbonate          4.5     g                                           Water   q.s.p.            100     g                                           ______________________________________                                    

The solution (pH=7.4) is stirred for 20 days under nitrogen at ambienttemperature. The oily product which has deposited at the bottom of thereaction medium is separated off by decantation, it is washed with adilute aqueous solution of sodium sulphite, and 45 ml of absoluteethanol, which has been saturated with hydrogen chloride and dilutedwith the same volume of a solution of sulphuric acid in ether, are thenadded thereto. The expected diphenylamine precipitates in the form ofthe crystalline dihydrochloride which melts at about 190° C. withdecomposition.

EXAMPLE 4 Preparation of2,4-dihydroxy-5methyl-4'-tetrahydrofurfurylaminodiphenylaminedihydrochloride ##STR10##

6.16 g (0.04 mol) of 4-amino-N-tetrahydrofurfurylaniline dihydrochlorideare dissolved in 200 ml of boiled water containing 8 g of sodiumcarbonate and 2 g of sodium sulphite. The solution is kept in theabsence of air for 8 days at 40° C. The expected product hasprecipitated in the form of a gummy product. The supernatant liquid isdecanted and 8 ml of hydrochloric acid (d=1.19) are added immediately.The expected dihydrochloride crystallises immediately. The product isfiltered off and then recrystallised twice from 5 N hydrochloric acid.After drying in vacuo, the product melts at about 185° C. withdecomposition.

Elementary analysis of the product obtained gives the following results:

    ______________________________________                                                  CALCULATED                                                          ANALYSIS  FOR C.sub.18 H.sub.22 N.sub.2 O.sub.3 . 2HCl                                                   FOUND                                              ______________________________________                                        C%        55.82            55.66                                              H%        6.25             6.04                                               N%        7.23             7.02                                               C1%       18.31            18.17                                              ______________________________________                                    

EXAMPLE 5 Preparation of 2,4-dihydroxy-4'-piperidinodiphenylamine##STR11##

The following solution is prepared:

    ______________________________________                                        Trihydroxybenzene           9      g                                          N-(4-Aminophenyl)-piperidine dihydrochloride                                                              14.8   g                                          Sodium sulphite             4      g                                          Ethanol                     113    g                                          Triethanolamine             9.6    g                                          Water   q.s.p.              262    g                                          ______________________________________                                    

This solution (pH=8) is kept in the absence of air for 15 days at 25° C.After 3 days, the expected diphenylamine begins to precipitate in theform of white crystals. After keeping the mixture for 15 days underanaerobic conditions, the crystals are filtered off and washed with adilute solution of sodium sulphite and then with a small amount ofdistilled water. After drying in vacuo, the product melts at 176° C.

Elementary analysis of the product obtained gives the following results:

    ______________________________________                                                  CALCULATED                                                          ANALYSIS  FOR C.sub.17 H.sub.20 N.sub.2 O.sub.2                                                          FOUND                                              ______________________________________                                        C%        71.80            71.53                                              H%        7.09             7.11                                               N%        9.85             9.68                                               ______________________________________                                    

EXAMPLE 6 Preparation of 2,4-dihydroxy-4'-morpholinodiphenylamine##STR12##

The following solution is prepared:

    ______________________________________                                        Trihydroxybenzene       0.6     g                                             N-(4-Aminophenyl)-morpholine                                                                          0.85    g                                             Sodium sulphite         0.03    g                                             Ethanol                 6       g                                             Triethanolamine         0.1     g                                             Water   q.s.p.          24      g                                             ______________________________________                                    

This solution (pH=8) is kept in the absence of air for 15 days at 40° C.After 3 days, the expected diphenylamine starts to precipitate incrystalline form. After keeping the mixture for 15 days under anaerobicconditions, the crystals are filtered off, washed with a dilute solutionof sodium sulphite and then with a small amount of distilled water anddried in vacuo. After recrystallisation from 95° strength ethanol anddrying in vacuo, the product melts at 223° C.

Elementary analysis of the product obtained gives the following results:

    ______________________________________                                        ANALYSIS CALCULATED FOR C.sub.16 H.sub.18 N.sub.2 O.sub.3                                                     FOUND                                         ______________________________________                                        C%       67.11                  66.90                                         H%       6.34                   6.47                                          N%       9.78                   9.93                                          ______________________________________                                    

EXAMPLE 7

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 2 1      g                                                Ethanol (96° strength)                                                                       20     g                                                Triethanolamine       10     g                                                Water q.s.p.          100    g                                                ______________________________________                                    

The pH of this composition is equal to 8.5.

When applied to bleached hair for 20 minutes at ambient temperature,this mixture imparts to the hair, after rinsing and shampooing, a lightcyclamen colouration.

EXAMPLE 8

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 2 1      g                                                Ethanol (96° strength)                                                                       20     g                                                Triethanolamine       10     g                                                Water q.s.p.          100    g                                                ______________________________________                                    

The pH of this composition is equal to 8.5.

25 g of hydrogen peroxide of 20 volumes strength are added at the timeof use.

When applied to bleached hair for 20 minutes at ambient temperature,this mixture imparts to the hair, after rinsing and shampooing, aprincess grey colouration.

EXAMPLE 9

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 1     0.8      g                                          Butylglycol               5        g                                          Oxyethyleneated lauryl alcohol containing                                     10.5 mols of ethylene oxide (per mol of alcohol).                                                       5        g                                          Triethanolamine           6        g                                          Water q.s.p.              100      g                                          ______________________________________                                    

The pH of this composition is equal to 8.5.

When applied to naturally white hair for 25 minutes at 25° C., thismixture imparts to the hair, after rinsing and shampooing, a dove greycolouration.

EXAMPLE 10

The following solution is prepared:

    ______________________________________                                        Compound of Example 1      0.2     g                                          Polyvinylpyrrolidone (mean molecular weight =                                 40,000) sold under the code                                                   K 30 by the Company                                                           "GENERAL ANILINE AND                                                          FILM CORPORATION"          2       g                                          Isopropanol                25      g                                          Triethanolamine (in 20 % strength aqueous)                                    solution)                  2.3     g                                          Water q.s.p.               100     g                                          ______________________________________                                    

Polyvinylpyrrolidone (mean molecular weight=40,000) sold under the codeK 30 by the Company

When applied as a wavesetting lotion to bleached hair, this solution(pH=8) imparts to the hair, after drying with hot air, a beigecolouration with a purple pink shade.

EXAMPLE 11

The following solution is prepared:

    ______________________________________                                        Compound of Example 5    0.2    g                                             Vinyl acetate/crotonic acid copolymer                                         (vinyl acetate 90 %, crotonic acid 10%)                                       (molecular weight = 45,000 to 50,000)                                                                  2      g                                             Ethanol (96° strength)                                                                          50     g                                             Triethanolamine          6      g                                             Water q.s.p.             100    g                                             ______________________________________                                    

When applied as a wavesetting lotion to bleached hair, this solution(pH=9) imparts to the hair, after drying with hot air, a pearlescentbeige colouration with a pinkish sheen.

EXAMPLE 12

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 5 1.5    g                                                Butylglycol           5      g                                                Isopropanol           20     g                                                Triethanolamine       5      g                                                Water q.s.p.          100    g                                                ______________________________________                                    

The pH of this composition is equal to 9.2.

When applied to bleached hair for 20 minutes at 27° C., this mixtureimparts to the hair, after rinsing and shampooing, an ashen beigecolouration with a purple-violet shade.

EXAMPLE 13

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 3    2      g                                             Sodium lauryl-sulphate containing 19% of                                      starting oxyethyleneated alcohol                                                                       20     g                                             Etylenediaminetetraacetic acid                                                                         0.1    g                                             Butylglycol              6      g                                             Sodium bisulphite solution (40% strength)                                                              1      g                                             Triethanolamine          4      g                                             Water q.s.p.             100    g                                             ______________________________________                                    

The pH of this composition is equal to 8.2.

When applied to 90% naturally white hair for 30 minutes at 25° C., thismixture imparts to the hair, after rinsing and shampooing, a silver greycolouration with a slight violet sheen.

EXAMPLE 14

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 3    2      g                                             Sodium lauryl-sulphate containing 19% of                                      starting oxyethyleneated alcohol                                                                       20     g                                             Etylenediaminetetraacetic acid                                                                         0.1    g                                             Butylglycol              6      g                                             Sodium bisulphite solution (40% strength)                                                              1      g                                             Triethanolamine          4      g                                             Water q.s.p.             100    g                                             ______________________________________                                    

The pH of this composition is equal to 8.2.

30 g of hydrogen peroxide of 20 volumes strength are added at the timeof use.

When applied to bleached hair for 25 minutes at 25° C., this mixtureimparts to the hair, after rinsing and shampooing, a pearlescent, ashenbeige colouration.

EXAMPLE 15

The following solution is prepared:

    ______________________________________                                        Compound of Example 6    0.17    g                                            Vinyl acetate/crotonic acid copolymer (vinyl                                  acetate 90%, crotonic acid 10%) (molecular                                    weight = 45,000 to 50,000)                                                                             2       g                                            Ethanol (96° strength)                                                                          50      g                                            Triethanolamine          2       g                                            Water q.s.p.             100     g                                            ______________________________________                                    

The pH of this composition is equal to 8.2.

When applied as a wavesetting lotion to bleached hair, this solutionimparts to the hair, after drying with hot air, a golden light blondcolouration with a pink sheen.

EXAMPLE 16

The following dyeing composition is prepared:

    ______________________________________                                        Comound of Example 6                                                                              1        g                                                Butylglycol         10       g                                                Ethanol (96° strength)                                                                     6        g                                                Carboxymethylcellulose                                                                            4        g                                                Triethanolamine     4        g                                                Water   q.s.p.      100      g                                                ______________________________________                                    

The pH of this composition is equal to 9.4.

When applied to bleached hair for 20 minutes at ambient temperature,this mixture imparts to the hair, after rinsing and shampooing, apinkish champagne colouration.

EXAMPLE 17

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 4                                                                             1.16     g                                                Ethanol (96° strength)                                                                     20       g                                                Triethanolamine     2        g                                                Water   q.s.p.      100      g                                                ______________________________________                                    

The pH of this composition is equal to 8.

When applied to bleached hair for 30 minutes at 30° C., this mixtureimparts to the hair, after rinsing and shampooing, a purple colouration.

EXAMPLE 18

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 2       1      g                                          Compound of Example 3       0.52   g                                          4,4'-Dihydroxy-3'-methyl-6'-aminodiphenylamine                                                            1      g                                          2,5-Diamino-4-methylphenol dihydrochloride                                                                0.3    g                                          Butylglycol                 5      g                                          Oxyethyleneated lauryl alcohol containing 10.5 mols                           of ethylene oxide           5      g                                          Triethanolamine             3.5    g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

The pH of this composition is equal to 7.9.

When applied to 90% naturally white hair for 20 minutes at 25° C., thismixture imparts to the hair, after rinsing and shampooing, an ashenlight chestnut colouration.

EXAMPLE 19

The following solution is prepared:

    ______________________________________                                        Compound of Example 3       0.5    g                                          Compound of Example 2       0.4    g                                          3-Nitro-4-aminophenol       0.065  g                                          Vinylpyrrolidone (70%)/vinyl acetate (30%)                                    polymer sold under the code PVP/VA E 735 by the                               Company "GENERAL ANILINE AND                                                                              3      g                                          FILM CORPORATION".                                                            Ethanol                     25     g                                          Triethanolamine             1      g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

The pH of this composition is equal to 7.2.

When applied as a wavesetting lotion to bleached hair, this solutionimparts to the hair, after drying with hot air, a copper redcolouration.

EXAMPLE 20

The following solution is prepared:

    ______________________________________                                        Compound of Example 3       0.5    g                                          Compound of Example 1       0.15   g                                          4,4'-Dihydroxy-3'-methyl-6'-aminodiphenylamine.                                                           0.3    g                                          Vinylpyrrolidone (60%)/vinyl acetate (40%)                                    copolymer sold under the code PVP/PA S 630 by                                 the Company "GENERAL ANILINE AND FILM                                         CORPORATION"                2      g                                          Isopropaol                  35     g                                          Triethanolamine             2.3    g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

When applied as a wavesetting lotion to bleached hair for 10 minutes atambient temperature, this solution (pH=8) imparts to the hair, afterdrying with hot air, a light brown colouration.

EXAMPLE 21

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 2      2       g                                          Para-aminophenol           0.15    g                                          2-N-(β-Hydroxyethylamino)-4-aminophenoxy-                                ethanol dihydrochloride    0.05    g                                          2-Methyl-5-aminophenol     0.15    g                                          Oxyethyleneated oleyl alcohol containing 2 mols                               of ethylene oxide          5       g                                          Oxyethyleneated oleyl alcohol containing 4 mols                               of ethylene oxide          10      g                                          Propylene glycol           10      g                                          Triethanolamine            8       g                                          Water   q.s.p.             100     g                                          ______________________________________                                    

The pH of this composition is equal to 8.4.

20 g of hydrogen peroxide of 20 volumes strength are added at the timeof use.

When applied to bleached hair for 20 minutes at 25° C., this mixtureimparts to the hair, after rinsing and shampooing, an ashen beigecolouration with a pink shade.

EXAMPLE 22

The following solution is prepared:

    ______________________________________                                        Compound of Example 5       0.5    g                                          4,4'-Dihydroxy-3'-methyl-6'-aminodiphenylamine                                                            0.5    g                                          3-Nitro-4-N'-(β-hydroxyethylamino)-N,N-(β-hydroxy-                  ethyl)-aniline              0.15   g                                          Isopropanol                 26     g                                          Quaternary vinylpyrrolidone copolymer                                         solid under the code "GAFquat 734" by the                                     Societe "GENERAL ANILINE FRANCE"                                              in a 50%                                                                      strength solution in alcohol (mean molecular                                  weight = 100,000)           1.6    g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

The pH of this solution is equal to 9.5.

When applied as a wavesetting lotion to bleached hair for 10 minutes at25° C., this solution imparts to the hair, after drying with hot air, amahogany colouration.

EXAMPLE 23

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 1       1.2    g                                          4-N,N-(β-Hydroxyethylamino)-3'-methyl-4-hydroxy-                         6'-aminodiphenylamine       0.7    g                                          3-Nitro-6-N-(β-hydroxyethylamino)-anisole                                                            0.05   g                                          3-Nitro-4-N'-methylamino-N,N-(β-hydroxyethyl)-                           aniline                     0.8    g                                          Butylglycol                 15     g                                          Diethanolamides of copra fatty acids                                                                      7.5    g                                          Triethanolamine             8      g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

The pH of this composition is equal to 8.7.

When applied to naturally white hair for 20 minutes at 25° C., thismixture imparts to the hair, after rinsing and shampooing, a veryluminous silvery grey colouration.

EXAMPLE 24

The following dyeing composition is prepared:

    ______________________________________                                        Compound of Example 1     2       g                                           Compound of Example 5     0.7     g                                           2-Hydroxy-1,4-naphthoquinone                                                                            1.5     g                                           Sodium lauryl-sulphate containing 19 %                                        of starting oxyethyleneated alcohol                                                                     20      g                                           Ethylenediaminetetraacetic acid                                                                         0.1     g                                           Triethanolamine           5       g                                           Sodium bisulphite solution (40 % strength)                                                              1       g                                           Water   q.s.p.            100     g                                           ______________________________________                                    

The pH of this composition is equal to 8.

When applied to bleached hair for 20 minutes at 25° C., this mixtureimparts to the hair, after rinsing and shampooing, a coppery chestnutcolouration.

EXAMPLE 25

The following dyeing composition is prepared:

    ______________________________________                                        4-N-(β-Methoxyethylamino)-aniline dihydrochloride                                                    3.8    g                                          Trihydroxybenzene           2      g                                          Ethanol (96° strength)                                                                             20     g                                          Sodium sulphite             0.1    g                                          Triethanolamine             11.8   g                                          Water   q.s.p.              100    g                                          ______________________________________                                    

After keeping this mixture for one month under anaerobic conditions(during which time the product of Example 1 appears in the saidmixture), 30 g of hydrogen peroxide of 20 volumes strength are addedthereto and it is applied to bleached hair for 25 minutes at ambienttemperature. After rinsing and shampooing, an extremely dark purpleviolet colouration is obtained.

EXAMPLE 26

The following dyeing composition is prepared:

    ______________________________________                                        4'-N-Furfurylaminoaniline dihydrochloride                                                               4.24     g                                          Trihydroxybenzene         2        g                                          Sodium sulphite           0.1      g                                          Triethanolamine           11       g                                          Ethanol                   20       g                                          Water   q.s.p.            100      g                                          ______________________________________                                    

The pH of this composition is equal to 8.2.

After keeping this mixture for one month under anaerobic conditions(during which time the product of Example 3 appears in the saidmixture), 30 g of ethanol are added thereto. The mixture is then appliedto 90% naturally white hair for 20 minutes at 25° C. After rinsing andshampooing, a very luminous silver grey colouration with a slight violetshade is obtained.

EXAMPLE 27

If, after keeping the mixture of the preceding Example for one month inthe absence of air, initially 30 g of ethanol and then 30 g of hydrogenperoxide of 20 volumes strength are added thereto, and if the dyeingcomposition is applied to 90% naturally white hair for 20 minutes at 25°C., a dark violet grey colouration is obtained after rinsing andshampooing.

We claim:
 1. A 2,4-dihydroxydiphenylamine of the formula: ##STR13## oran acid addition salt thereof, in which formula R₁ represents a hydrogenatom, R₂ represents a tetrahydrofurfuryl or methoxyethyl radical and Rrepresents a hydrogen atom or a methyl radical.
 2. Adihydroxydiphenylamine according to claim 1 which is2,4-dihydroxy-4'-N-(β-methoxyethylamino)-diphenylamine dihydrochloride.3. A dihydroxydiphenylamine according to claim 1 which is2,4-dihydroxy-5-methyl-4'-N-(β-methoxyethylamino)-diphenylaminedihydrochloride.
 4. A dihydroxy diphenylamine according to claim 1 whichis 2,4-dihydroxy-4'-tetrahydrofurfurylaminodiphenylaminedihydrochloride.
 5. A dihydroxy diphenylamine according to claim 1 whichis 2,4-dihydroxy-5-methyl-4'-tetrahydrofurfurylamino diphenylamine.